Gas Power

Gas power

GasPower limits the GasLimit of transactions and events, which a validator may originate.

The underlying mechanism is based on MedianTime. The allocated gas power is proportional to the amount of time that has passed since previous event, whose time is measured in MedianTime. It isn't possible to bias the MedianTime, unless more than 1/2W of the network collude about the shift of time.

Gas power windows

Gas power has 2 windows - long term window and short term window, each of them has its own set of constants. The formulas work the same for each window, and only window constants differ.

• Long-term window increases slowly, but has a high maximum accumulated value. This window controls an average load (txs and events per second).
• Short-term window increases rapidly, but has a low maximum accumulated value. This window controls load peaks (txs and events per second).

Exact formula for each window

Constants for each validator:

• TotalPerH = determines the gas power allocation per hour in the whole network.
• validator’s gas per hour = TotalPerH * validator’s stake / total stake.
• max gas power = validator’s gas per hour * MaxStashedPeriod.
• startup gas = max(validator’s gas per hour * StartupPeriod, MinStartupGasPower).

if {e.SelfParent} != nil
    {prev gas left} = e.SelfParent.GasPowerLeft
    {prev median time} = e.SelfParent.MedianTime
else if prevEpoch.LastConfirmedEvent[validator] exists
    {prev gas left} = max(prevEpoch.LastConfirmedEvent[validator].GasPowerLeft, {startup gas})
    {prev median time} = prevEpoch.LastConfirmedEvent[validator].MedianTime
else
    {gas stashed} = {startup gas}
    {prev median time} = prevEpoch.Time
{gas power allocated} = ({e.MedianTime} - {prev median time}) * {validator’s gas per hour} / hour
{GasPower} = {prev gas left} + {gas power allocated}
if {GasPower} > {max gas power}
    {GasPower} = {max gas power}
{e.GasPowerLeft} = {GasPower} - {e.GasPowerUsed}

return {GasPower}, {e.GasPowerLeft}